Multiplexed amplitude-phase modulation for 5G/6G noise mitigation

Abstract

Phase noise is a limiting factor in high-frequency 5G and 6G communications. Disclosed is a multiplexed amplitude-phase modulation scheme that can provide extremely wide phase noise margins at high frequencies. The transmitter can transmit a wave modulated in amplitude and phase, configured to provide a wide separation of phase states. The receiver, on the other hand, demodulates the message using quadrature amplitude modulation QAM, since that is generally more economical and technically preferred for signal processing. The demodulated message, however, still retains the large phase margins. As a further benefit, the examples illustrate non-square and asymmetric modulation schemes, which can extend the noise margins even further. By modulating with amplitude and phase, but demodulating with orthogonal branch signals, wireless networks can expand into high-frequency bandwidths while retaining high reliability and high throughput, as required for wireless applications of tomorrow.

The invention claimed is: 
     
       1. A method for a wireless receiver to demodulate a message, the method comprising:
 a) receiving a message comprising message elements, each message element modulated, by a transmitter, according to a first modulation scheme, wherein the first modulation scheme comprises, for each message element, amplitude modulation multiplexed with phase modulation; and 
 b) demodulating each message element according to a second modulation scheme different from the first modulation scheme, wherein the second modulation scheme comprises, for each message element, QAM (quadrature amplitude modulation) comprising a first branch signal and an orthogonal second branch signal, wherein: 
 c) the first modulation scheme further comprises at least three predetermined amplitude levels; 
 d) wherein the amplitude modulation is according to the at least three predetermined amplitude levels; and 
 e) wherein the at least three predetermined amplitude levels are equally spaced apart. 
 
     
     
       2. The method of  claim 1 , wherein the message is configured according to 5G or 6G technology. 
     
     
       3. The method of  claim 1 , wherein:
 a) the first modulation scheme further comprises at least two predetermined phase levels; 
 b) wherein the phase modulation is according to the at least two predetermined phase levels; and 
 c) wherein the at least two predetermined phase levels are equally spaced apart. 
 
     
     
       4. A method for a wireless receiver to demodulate a message, the method comprising:
 a) receiving a message comprising message elements, each message element modulated, by a transmitter, according to a first modulation scheme, wherein the first modulation scheme comprises, for each message element, amplitude modulation multiplexed with phase modulation; and 
 b) demodulating each message element according to a second modulation scheme different from the first modulation scheme, wherein the second modulation scheme comprises, for each message element, QAM (quadrature amplitude modulation) comprising a first branch signal and an orthogonal second branch signal, wherein: 
 c) the first modulation scheme further comprises amplitude modulation according to integer Namp predetermined amplitude levels; 
 d) the first modulation scheme further comprises phase modulation according to integer Nphase predetermined phase levels; and 
 e) Namp is different from Nphase. 
 
     
     
       5. A method for a wireless receiver to demodulate a message, the method comprising:
 a) receiving a message comprising message elements, each message element modulated, by a transmitter, according to a first modulation scheme, wherein the first modulation scheme comprises, for each message element, amplitude modulation multiplexed with phase modulation; and 
 b) demodulating each message element according to a second modulation scheme different from the first modulation scheme, wherein the second modulation scheme comprises, for each message element, QAM (quadrature amplitude modulation) comprising a first branch signal and an orthogonal second branch signal, wherein: 
 c) the second modulation scheme further comprises at least three predetermined branch amplitude levels; and 
 d) the second modulation scheme further comprises demodulating each message element according to the at least three predetermined branch amplitude levels. 
 
     
     
       6. The method of  claim 5 , further comprising:
 a) for each message element, determining a first received branch amplitude of the first branch signal; and 
 b) for each message element, determining a second received branch amplitude of the second branch signal. 
 
     
     
       7. The method of  claim 6 , further comprising:
 a) receiving a demodulation reference comprising a maximum branch amplitude level of the at least three predetermined branch amplitude levels; and 
 b) determining, according to the maximum branch amplitude level, each predetermined branch amplitude level of the at least three predetermined branch amplitude levels. 
 
     
     
       8. The method of  claim 7 , further comprising:
 a) for each message element, determining which predetermined branch amplitude level, of the at least three predetermined branch amplitude levels, is closest to the first received branch amplitude; and 
 b) for each message element, determining which branch amplitude level, of the at least three predetermined branch amplitude levels, is closest to the second received branch amplitude. 
 
     
     
       9. The method of  claim 6 , further comprising:
 a) receiving a demodulation reference comprising a particular reference signal; 
 b) determining, according to the particular reference signal, a phase rotation angle associated with phase noise; and 
 c) for each message element of the message, correcting the first and second received branch amplitudes according to the phase rotation angle. 
 
     
     
       10. The method of  claim 6 , further comprising:
 a) receiving a demodulation reference comprising a particular resource element with no transmission therein; 
 b) determining, according to a noise signal received in the particular resource element, an amplitude shift; and 
 c) for each message element of the message, correcting the first and second received branch amplitudes according to the amplitude shift. 
 
     
     
       11. Non-transitory computer-readable media in a wireless transmitter, the media containing instructions that when implemented in a computing environment cause a method to be performed, the method comprising:
 a) determining or receiving a message to be transmitted, the message comprising message elements; 
 b) modulating each message element according to a first modulation scheme comprising amplitude modulation multiplexed with phase modulation, wherein the amplitude modulation is according to a plurality of predetermined amplitude levels and the phase modulation is according to a plurality of predetermined phase levels, wherein the predetermined amplitude levels are equally spaced apart and the predetermined phase levels are equally spaced apart; and 
 c) transmitting, for each message element, a sine wave comprising a wave amplitude and a wave phase, wherein the wave amplitude is modulated according to one of the predetermined amplitude levels, and wherein the wave phase is modulated according to one of the predetermined phase levels, wherein: 
 d) the predetermined amplitude levels comprise a maximum predetermined amplitude level; and 
 e) wherein the method further comprises transmitting, proximate to a beginning of the message, a demodulation reference comprising the maximum predetermined amplitude level. 
 
     
     
       12. Non-transitory computer-readable media in a wireless transmitter, the media containing instructions that when implemented in a computing environment cause a method to be performed, the method comprising:
 a) determining or receiving a message to be transmitted, the message comprising message elements; 
 b) modulating each message element according to a first modulation scheme comprising amplitude modulation multiplexed with phase modulation, wherein the amplitude modulation is according to a plurality of predetermined amplitude levels and the phase modulation is according to a plurality of predetermined phase levels, wherein the predetermined amplitude levels are equally spaced apart and the predetermined phase levels are equally spaced apart; and 
 c) transmitting, for each message element, a sine wave comprising a wave amplitude and a wave phase, wherein the wave amplitude is modulated according to one of the predetermined amplitude levels, and wherein the wave phase is modulated according to one of the predetermined phase levels, the method further comprising: 
 d) transmitting, proximate to a beginning of the message, a demodulation reference comprising a first resource element and a second resource element; 
 e) wherein the first resource element comprises a maximum predetermined amplitude level of the first modulation scheme; and 
 f) wherein the second resource element comprises no transmission therein. 
 
     
     
       13. Non-transitory computer-readable media in a wireless transmitter, the media containing instructions that when implemented in a computing environment cause a method to be performed, the method comprising:
 a) determining or receiving a message to be transmitted, the message comprising message elements; 
 b) modulating each message element according to a first modulation scheme comprising amplitude modulation multiplexed with phase modulation, wherein the amplitude modulation is according to a plurality of predetermined amplitude levels and the phase modulation is according to a plurality of predetermined phase levels, wherein the predetermined amplitude levels are equally spaced apart and the predetermined phase levels are equally spaced apart; and 
 c) transmitting, for each message element, a sine wave comprising a wave amplitude and a wave phase, wherein the wave amplitude is modulated according to one of the predetermined amplitude levels, and wherein the wave phase is modulated according to one of the predetermined phase levels, 
 d) wherein:
 i) the plurality of predetermined amplitude levels comprises Namp amplitude levels; 
 ii) the plurality of predetermined phase levels comprises Nphase phase levels; and 
 iii) Namp is not equal to Nphase; 
 
 and further comprising: 
 e) determining that a rate of phase faults is greater than a rate of amplitude faults; and 
 f) subsequently modulating messages using a third modulation scheme, wherein the third modulation scheme comprises less than Nphase phase levels and more than Namp amplitude levels. 
 
     
     
       14. A wireless receiver comprising circuitry configured to:
 a) receive a message comprising message elements, each message element comprising a sine wave, the sine wave comprising a wave amplitude and a wave phase, wherein the wave amplitude is modulated according to a plurality of predetermined wave amplitude levels and the wave phase is modulated according to a plurality of predetermined wave phase levels; 
 b) for each message element, determine an I-branch signal and an orthogonal Q-branch signal; and 
 c) for each message element, determine a message I-branch amplitude of the I-branch signal, and determine a message Q-branch amplitude of the Q-branch signal, further configured to: 
 d) receive a demodulation reference comprising a first resource element and a second resource element, wherein the first resource element comprises a particular transmission, and the second resource element comprises no transmission; 
 e) determine, according to the particular transmission, a reference I-branch amplitude and a reference Q-branch amplitude; 
 f) calculate a maximum branch amplitude comprising a square root of a sum of the reference I-branch amplitude squared plus the reference Q-branch amplitude squared; 
 g) calculate, according to the maximum branch amplitude, one or more additional branch amplitudes, wherein the maximum branch amplitude and the one or more additional branch amplitudes comprise a plurality of predetermined branch amplitude levels; and 
 h) for each message, demodulate the message element by comparing the message I-branch amplitude to the predetermined branch amplitude levels, and comparing the message Q-branch amplitude to the predetermined amplitude levels. 
 
     
     
       15. The wireless receiver of  claim 14 , further configured to:
 a) determine, according to a ratio of the reference Q-branch amplitude divided by the reference I-branch amplitude, a phase rotation angle; 
 b) for each message element, determine a corrected I-branch amplitude and a corrected Q-branch amplitude by de-rotating the I-branch signal and the Q-branch signal by the phase rotation angle. 
 
     
     
       16. The wireless receiver of  claim 14 , further configured to:
 a) determine, according to the reference I-branch amplitude and the reference Q-branch amplitude, an amplitude shift; 
 b) for each message element, determine a corrected I-branch amplitude and a corrected Q-branch amplitude by shifting the I-branch signal and the Q-branch signal opposite to the amplitude shift.